Keith Mitchell opened Thursday’s U.S. Open at Shinnecock Hills with a double‑bogey 6 after a hooked tee shot. By the turn he stood six strokes over par, a stark contrast to the front‑nine heroics that followed.

From the first tee, Mitchell carved a 29‑hole run, the lowest front‑nine in U.S. Open history and only the seventh such score ever. Three early birdies and an eagle on the par‑5 fifth made the 6‑under 29 historic.

The record‑breaking front nine came against a backdrop of a 40‑plus score on the back. Mitchell’s 29‑hole run places him uniquely in the 126‑year tournament record books, a feat never seen before in a single round.

At even‑par 70, Mitchell sat two strokes behind early clubhouse leader Sam Stevens, a margin that shrank as his turnaround unfolded. The performance underscores the volatility of U.S. Open play and cements Mitchell’s name in the event’s lore.